forwarded message re: tiles

updated wed 27 jan 99

ARTMOLIN@ACS.EKU.EDU on tue 26 jan 99

From: Ann Stecker

************************************

I would be most grateful for any help with optimum firing schedules for
lowfire relief tiles.

I fired some test tiles for a relief mural and had everyone of them
crack. The tiles in the lowest part of the kiln not only cracked,
but were actually moved apart.(A large platter with even thickness, same
clay, fired perfectly on a shelf under the tiles) I'm
using Clayart Extra White low fire clay with sand. I bisqued to 05 and
glazed to 05. These were painted with commercial
underglazes and a Mayco commercial clear glaze. The tiles are 6" x 6"
and the relief is nearly 1 " in some areas with other
areas at 3/4" - 1/2" - 3/8". They were fired very slowly, but without a
controller. I was told by Clayart that it sounds like the
cooling was too rapid. So.......I purchased a Scutt KilnMaster
Controller. I asked Clayart and Scutt for recommendations for
a firing schedule for this project. They recommended different
schedules and I would like a recommendation for which
schedule is the best to use, or another schedule that would be better.
Do I need to fire the low-fire clay higher on the bisque
and why? Many thanks in advance for any and all help.